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1.
The tensile load strength of a glass-ionomer cement to untreated, etched, and citric acid-cleansed enamel, dentin, and cementum was measured. This study also tested one material for which neither conditioning nor etching was recommended by the manufacturer.  相似文献   

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This in vitro study compared the shear bond strength of a resin-modified glass-ionomer restorative material (Fuji II LC) bonded to saliva-contaminated dentin versus non-contaminated dentin. Seventy-five extracted human molar teeth were randomly divided into five groups of 15 samples each. The dentin was treated with 10% polyacrylic acid for 20 seconds, rinsed, and dried. The acid-treated dentin surfaces in Groups 1-4 were contaminated with saliva. In Group 1, the saliva was air thinned. In Groups 2-4, saliva was dried completely with compressed air. The saliva-contaminated dentin in Group 3 was rinsed and dried. The saliva-contaminated dentin in Group 4 was rinsed, dried, treated with 10% polyacrylic acid, and dried. Specimens in Group 5 received no contamination. The resin-modified glass-ionomer cement restorative material was mixed and applied to the dentin surfaces. Following placement of the restorative material and 7 days of storage, the specimens were thermo-cycled 300 times. Using the Instron Universal Testing Machine, a shear force was applied to the restorative material. Shear bond strength values were compared among the groups using a one-way ANOVA and Student-Neuman-Keuls Multiple Range Test (alpha = 0.05). The non-contaminated specimens (Group 5) were significantly stronger than the contaminated specimens (Groups 1-4). There were no significant differences in bond strength among the groups containing contaminated specimens. Salivary contamination occurring after dentin etching significantly reduced the bond strength of the resin-modified glass-ionomer restorative material to dentin. Neither rinsing nor rinsing and re-etching resulted in bond strengths as great as to non-contaminated dentin.  相似文献   

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Removal of the dentinal smear layer prior to placement of glass-ionomer cement is thought to maximize the strength of glass-ionomer cement/dentin bonding. This study evaluated the effect of three polyacrylic acid pretreatments on bond shear strength between glass-ionomer cement and dentin. Extracted human molars were divided into four groups of 30 specimens each. One group (the control) received no pretreatment. Specimens in the remaining groups were pretreated with one of three commercially available polyacrylic acid conditioners, used according to the manufacturers' recommendations. The results indicated significant differences in shear strength among pretreatment conditions. Since the manufacturers' recommendations varied, it is not clear if these results were due to differences in polyacrylic acid concentration or to other factors, such as application time or placement procedure.  相似文献   

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PURPOSE: The purpose of this study was to evaluate the influence of alloy surface microabrasion, silica coating, or microabrasion plus tin plating on the tensile bond strengths between a resin-modified glass-ionomer luting cement and a high-noble alloy. Bond strength between the microabraded alloy specimens and conventional glass-ionomer cement or resin cement were included for comparison. MATERIALS AND METHODS: One hundred twenty uniform size, disk-shaped specimens were cast in a noble metal alloy and divided into 6 groups (n = 10 pairs/group). The metal surfaces of the specimens in each group were treated and cemented as follows. Group 1: No surface treatment (as cast, control), cemented with a resin-modified glass-ionomer cement. Group 2: Microabrasion with 50-microm aluminum oxide particles, resin-modified glass-ionomer cement. Group 3: A laboratory microabrasion and silica coating system, resin-modified glass-ionomer cement. Group 4: Microabrasion and tin-plating, resin-modified glass-ionomer cement. Group 5: Microabrasion only, conventional glass-ionomer cement. Group 6: Microabrasion and tin-plating, conventional resin cement. The uniaxial tensile bond strength for each specimen pair was determined using an Instron Universal Testing Machine (Instron Corp, Canton, MA). Results were analyzed using a one-way analysis of variance (alpha = 0.05) and a Tukey post-hoc analysis. RESULTS: Mean bond strength: Group 1: 3.6 (+/- 1.5) MPa. Group 2: 4.2 (+/-0.5) MPa. Group 3: 6.7 (+/- 0.9) MPa. Group 4: 10.6 (+/- 1.8) MPa. Group 5: 1.1 (+/- 0.4) MPa. Group 6: 14.6 (+/- 2.3) MPa. Group 6 was significantly stronger than Group 4. The bond strength of specimens cemented with the resin-modified glass-ionomer cement using microabrasion and tin-plating (Group 4) was significantly stronger than all other groups except the resin cement with microabrasion and tin-plating (Group 6). CONCLUSION: Microabraded and tin-plated alloy specimens luted with the resin-modified glass-ionomer cement resulted in the greatest mean tensile strengths for the resin-modified glass-ionomer cement groups. This strength was 73% of the mean tensile strength of microabraded specimens luted with resin cement.  相似文献   

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The purpose of this study was to compare the shear bond strength to composite resin of a light-curing glass-ionomer cement with that of various chemically curing glass-ionomer cements. Light-cured composite resin cylinders were bonded to cylindrical glass-ionomer substrates after etching for 30 seconds with 37% phosphoric acid. Specimens were maintained in distilled water for 7 days and then thermocycled in water baths. One group of light-cured glass-ionomer cement substrates was not etched. The interfacial bond strength of these specimens was measured in shear. Cement shear strength was also evaluated. Statistical analysis showed the light-curing cement to have a significantly higher bond strength to composite resin than any of the chemically curing cements tested.  相似文献   

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玻璃离子水门汀与银汞粘接的剪切力测试   总被引:2,自引:0,他引:2  
探讨了玻璃离子水门汀增强银汞充填体与牙体之间的粘结作用。取新鲜离体人磨牙制成3mm厚的牙块,在其中央制备直径3mm的圆柱形洞,分别以玻璃离子、银汞粘结剂涂于洞壁,再充填银汞合金,另设空白对照组。两周后测各组的剪切力并作统计学分析。结果表明:玻璃离子与银汞粘结剂组的剪切力比空白对照组大,并有显著差异;说明玻璃离子与银汞粘结剂均有相似的增强银汞修复体与牙体之间粘结力的作用。  相似文献   

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ObjectiveA glass-ionomer cement (GIC) containing BioUnion filler has been reported to release Zn2+ under acidic conditions and to inhibit oral bacteria on its surface. However, previous results are based on in vitro experiments under static conditions. This study aimed to assemble an in vitro saliva-drop setting to simulate in vivo conditions of the oral cavity and to investigate the ion releasing and recharging properties of the GIC containing BioUnion filler.MethodsThe effective concentrations of Zn2+ and F? against Streptococcus mutans and saliva-derived multi-species biofilms were determined. Artificial saliva was dropped on the GIC containing BioUnion filler using the in vitro saliva-drop setting assembly and was periodically replaced with acetic acid. Ion release/recharge properties were investigated by measuring the release concentrations of Zn2+ and F?.ResultsThe concentration of Zn2+ released from the BioUnion filler-containing GIC during seven days with repeated exposure to acid could be maintained at the level to inhibit S. mutans and saliva-derived multi-species biofilm formation. Moreover, the BioUnion filler-containing GIC could be recharged with Zn2+ and F? by the application of a tooth gel containing Zn2+ and F?. The release concentration of Zn2+ after recharging was significantly higher than the effective concentration of Zn2+ to hinder S. mutans and saliva-derived multi-species biofilm formation on material surfaces.SignificanceThe GIC containing BioUnion filler was shown to have the potential to inhibit biofilm formation in the oral cavity. In addition, recharging Zn2+ and F? would further enhance the effect of the GIC containing BioUnion filler.  相似文献   

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PURPOSE: The aim of this in vitro study was to evaluate the shear bond strength of two conventional glass-ionomer cements to bovine dentin when using the air-abrasion technique for cavity preparation. MATERIALS AND METHODS: Forty bovine central incisors were selected, embedded in polyester resin, and ground until the dentin surface was exposed. The teeth were randomly assigned to four groups: I and II--rotating instrument with a carbide bur; III and IV--an air-abrasion system. Groups I and III were restored with Fuji IX and groups II and IV with Ketac Molar. A 3-mm-diameter bonding site was delimited and treated with 10% polyacrylic acid for 10 s in the Fuji IX subgroups and with 25% polyacrylic acid for 10 s in the Ketac Molar subgroups. After surface treatment, a glassionomer cylinder was prepared for each specimen, using a split bisected Teflon matrix. The finished specimens were submitted to the shear bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed using ANOVA and Scheffé statistical tests. The dentin bonding areas were analyzed under a stereoscopic optical magnifier (40X) to assess the type of failure. RESULTS: The mean (SD) shear bond strengths in MPa were: group I--3.49 (+/- 3.77), group II--7.17 (+/- 2.93), group III--7.55 (+/- 2.99), group IV--5.67 (+/- 3.90). Ketac Molar showed higher bond strength values in bur-prepared cavities, while on the air-abraded preparations, Fuji IX showed superior results. CONCLUSION: It can be concluded that the air-abrasion system used for cavity preparations may influence the bonding performance of conventional glass-ionomer cements to dentin.  相似文献   

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ABSTRACT The advantages offered by glass-ionomer cements would be greatly extended if they formed an attachment to ceramic materials.  相似文献   

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The repair bond strength of three different brands of glass-ionomer restorative was tested over time. In this laboratory study, immediate repair of glass ionomer was possible with all three brands; however, over time the repair bond strengths decreased at different rates for the different materials.  相似文献   

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The bond strength between composites and various particle sizes of glass-ionomer cements was investigated. The best bond strength was obtained after use of a small-particle cement and with the highest powder-to-liquid ratio employed for mixing the cement. In addition, use of a small-particle cement and the highest powder:liquid ratio produced cements with significantly stronger tensile strengths. Failure usually occurred within the cement. Consequently, the recorded bond strength actually reflected the tensile strength of the relevant cement.  相似文献   

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